cosmopolitan/libc/calls/gettimeofday-sysv.S
Justine Tunney 23d333c090 Make more improvements
This change includes many bug fixes, for the NT polyfills, strings,
memory, boot, and math libraries which were discovered by adding more
tools for recreational programming, such as PC emulation. Lemon has also
been vendored because it works so well at parsing languages.
2020-09-28 01:20:34 -07:00

54 lines
2.6 KiB
ArmAsm

/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8 -*-│
vi: set et ft=asm ts=8 tw=8 fenc=utf-8 :vi
Copyright 2020 Justine Alexandra Roberts Tunney
This program is free software; you can redistribute it and/or modify │
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License. │
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of │
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software │
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
*/
#include "libc/dce.h"
#include "libc/macros.h"
/ Returns system wall time in microseconds.
/
/ @param rdi points to timeval that receives result
/ @param rsi receives UTC timezone if non-NULL
/ @return always zero
/ @see clock_gettime() for nanosecond precision
/ @see strftime() for string formatting
gettimeofday$sysv:
push %rbp
mov %rsp,%rbp
.profilable
test %rsi,%rsi
jz 1f
push $0
pop (%rsi)
1: xor %esi,%esi # no one zones this way.
xor %edx,%edx # i64*mach_absolute_time
call __gettimeofday$sysv
#if SupportsXnu()
testb IsXnu() # XNU might do %rax:%rdx
jz 1f
test %rdi,%rdi
jz 1f
test %rax,%rax
jz 1f
mov %rax,(%rdi)
mov %rdx,8(%rdi)
#endif
1: xor %eax,%eax # nevar fail
pop %rbp
ret
.endfn gettimeofday$sysv,globl,hidden